Related, slightly: about 15 years ago, we were in a horrific auto accident: got rear-ended by a large sedan that was travelling about 45 mph. Anyone who saw our car afterwards couldn't believe that we survived. My C3,4,5 vertebrae were all damaged. Lots of nerve issues, tingly/numb arms, some leg issues, etc. Lots of doctor appointments and PT. At some point, I mentioned to the neurologist that I am a cyclist, and he remarked that it probably really hurt to be stretched out over the handlebar. "No," I replied. "That's about the only time I feel okay."

"Then you should ride more," he said.

Advice followed.